The present invention relates to an optical disk loading device in an optical disk reproducing apparatus for reproducing a signal on an optical disk such as an optical video disk, a digital audio disk, etc., in which a tray for mounting the optical disk thereon is horizontally moved and is then pulled into the reproducing apparatus and is thereafter vertically moved to move the optical disk onto a turntable.
In a conventional loading device of this kind, a cylindrical roller is inserted into a guide groove on a side face of the tray. Accordingly, if the tray is twisted or bent by an external force, parallelism between the circumferential face of the roller and the contact face of the guide groove is lost so that a portion of the roller moves or eats into the guide groove. Therefore, it becomes difficult to horizontally move the tray smoothly. Moreover, when the roller and the guide groove are deformed by such movement of the roller portion into the guide groove, a rattle is caused by the deformed portion during every loading operation, and the loading operation can no longer be performed smoothly.
In particular, such a problem often occurs when an elevating plate is disposed on only one side of the tray and a member for supporting the roller is raised and lowered on the other side of the tray in accordance with the raising and lowering movements of the elevating plate, or when the number of rollers is reduced.
Also, in the conventional loading device horizontal guide grooves are disposed on opposite sides of the tray on which the disk is mounted for reproduction. The tray is moved in the horizontal direction by guide members of elevating members disposed on the right and left sides of the tray to pull the tray into the reproducing apparatus. The elevating members on both sides of the tray are lowered in association with each other so that the tray is lowered while the horizontal state of the tray is maintained, thereby to lower the disk onto the turntable.
In this apparatus, it is necessary to dispose the elevating members on both sides of the tray and to provide a mechanism for operating the elevating members on the lower side of the tray. As a result, the space under the tray is entirely occupied and is not available for the mounting of electronic circuits or the like. This makes the overall size of the apparatus larger than desired.
The present invention further relates to an optical axis adjusting device for an optical-type pickup for aligning a straight line passing through the center of a turntable to a straight line passing through the optical axis of the pickup.
In a conventional pickup optical axis adjusting device, the spindle motor for the turntable is mounted such that the center of the turntable is positioned on an extension of a moving straight line defined by the optical axis of the pickup. In another device, the optical pickup is moved in a direction perpendicular to a guide shaft and is fixed to a support member such that the optical axis of the pickup is located on the center line of the turntable.
However, if in the conventional pickup optical axis adjusting device the spindle motor and the pickup are not premounted in a unitary assembly, these members can be freely moved relative to one another, and it is difficult for the assembly worker to align these members.
Further, since this adjustment must be performed after the assembly of the optical disk reproducing apparatus, it is difficult to fasten and unfasten the attaching screws of the spindle motor and the optical pickup.
The present invention still further relates to an optical axis adjusting device for an optical disk reproducing apparatus for reproducing information recorded on an optical disk such as an optical video disk, a digital audio disk, etc., which performs a tangential adjustment in which the optical axis of the optical pickup is made perpendicular to the surface of an optical disk in a plane perpendicular to a straight line passing through the center of a turntable.
A conventional optical pickup adjusting device for performing the tangential adjustment is shown in FIGS. 31 and 32. As shown in these figures, guide shaft 60 attached to a base plate guides optical pickup 62 fixed to attaching body 61 towards the outer circumference of the optical disk from the center thereof. Two fitting portions 61a and 61b of attaching body 61 are fitted to this guide shaft 60 and are guided thereby so that attaching body 61 is not inclined with respect to guide shaft 60. Screw 65 and pressure spring 66 are disposed on the opposite side of fitting portions 61a and 61bof the attaching body 61 and between attaching body 61 and slide piece 64 guided by guide piece 63 of the base plate.
Accordingly, when screw 65 is pressed against pressure spring 66, attaching body 61 is rotated around guide shaft 60 in the direction shown by an arrow in FIG. 32. Therefore, optical axis c of optical pickup 62 can be tilted leftward and rightward with respect to the face of the optical disk, thereby performing the tangential adjustment of the pickup.
In such a conventional pickup optical axis adjusting device, however, since the tangential adjustment is performed by setting the optical disk, screw 65 cannot be rotated from above so that the tangential adjustment must be performed from a lower or side face of the device.
Accordingly, when screw 65 is rotated from the side face of the device, it is very difficult for the operator to rotate this screw since the rotary center of the screw is perpendicular to the vertical direction.
To be able to carry out tangential adjustment from the lower face of the device, it is necessary to provide holes in several parts of the base plate, etc., and hence the mechanical strength these parts is reduced and the location for performing the adjustment thereof is limited.
The present invention yet further relates to a disk loading device of an optical disk reproducing apparatus for reproducing an optical disk such as an optical video disk or a digital audio disk in which the optical disk is mounted on a tray and the tray is pulled into the optical disk reproducing apparatus by a horizontal movement and then lowered and moved onto the turntable, and a clamper is lowered from above to clamp the optical disk between the turntable and the clamper.
A conventional disk loading device of this kind is operated by a cam mechanism for lowering the tray and a cam mechanism for raising and lowering a clamper support member attaching the clamper thereto. However, in the conventional loading device the tray is lowered and the clamping operation by the clamper is performed by separate cam mechanisms. Therefore, it is necessary to provide a mechanism for conforming the operating timings of the two cam mechanisms to each other. Further, it is necessary to provide a mechanism for holding the tray and the clamper in their positions after the tray has been moved and the clamping operation has been completed by the clamper.
When such a mechanism operates the tray and the clamper by movement through a small stroke, their operations sometimes cannot be smoothly performed due to differences in the dimensions thereof and their operating positions become unstable, thereby reducing the efficiency in operation.
If the stroke is increased to solve this problem, the size of the cam member is increased, making it is necessary to provide a large space installation space therefor, which makes it difficult to make the reproducing apparatus compact.
Furthermore, if the radial movement is efficiently converted to a linear movement, the structure is limited to a mechanism having a rack, pinion, etc.
The present invention also relates to a disk clamping device of an optical disk reproducing apparatus for clamping, on a turntable for rotating an optical disk such as an optical video disk, an optical audio disk, etc., the optical disk between the turntable and a clamper.
In a conventional disk clamping device, the clamper is rotatably attached through a ball member to an end of a clamper attaching plate pivotally supported at one end thereof. When the optical disk is clamped, the clamper is oriented parallel to the turntable. However, the clamper is supported approximately parallel to the clamper attaching plate except for the clamping time of the disk. That is, the clamper attaching plate is pivotally supported at one end thereof such that the clamper is parallel to the turntable when the optical disk is clamped. Accordingly, when no clamping operation is performed and the clamper is raised, the clamper attaching plate is inclined with respect to the turntable such that the end of the clamper attaching plate is inclined upward.
Thus, since the clamper is supported parallel to the clamper attaching plate, the clamper is also inclined at this time with respect to the turntable. When the optical disk is set on the turntable, it is necessary to have a certain amount of space between the turntable and the clamper. However, as mentioned above, since the clamper is inclined, the size between the turntable and the lowermost end of the inclined clamper is set to the size of the above space. Accordingly, the clamper must be unnecessarily raised by the amount of its inclination. Therefore, the rotary angle of the clamper attaching plate must be large and the distance through which it must be raised must be large, and thus, the height of the optical disk reproducing apparatus is correspondingly increased.
The invention still further relates to an optical disk player having a tilting device for maintaining a parallel relation between a moving straight line defined by the optical axis of the optical pickup thereof and the axis of movement of a clamper used to clamp the optical disk to the turntable and for maintaining the optical axis of the pickup perpendicular to the clamped disk. When a deviation from the perpendicular orientation is detected, the tilting device is driven so as to tilt the optical axis of the optical pickup in such a manner that the optical axis of the pickup is made to return to be perpendicular with respect to the surface of the disk.
In the conventional apparatus, the clamper and the tilting device were operated by separate and independent drive units. That is, separate motors were provided to separated drive a disk loading mechanism for pulling the optical disk into the player and placing and clamping it on the turntable and for maintaining the optical axis of the pickup vertical at all times with respect to the surface of the disk. Moreover, it was necessary to provide a separate mechanism for holding the clamper in position. As a result, the overall mechanism was complicated and often less reliable than desired. Also, the space required for the two separate motors was large.